This application is based on and claims priority under 35 U.S.C. xc2xa7119 with respect to Japanese Application No. 11-341193 filed on Nov. 30, 1999 and Japanese Application No. 2000-344117 filed on Nov. 10, 2000, the entire content of both of which is incorporated herein by reference.
The present invention generally relates to a vehicle seat. More particularly, the present invention pertains to a vertical movement apparatus for a vehicle seat.
A known vertical movement apparatus for a vehicle seat is disclosed in Unexamined Published Japanese Patent Application (Kokai) No. H10(1998)-338063. The vertical movement apparatus described in this document includes many links operatively assembled by many pivot pins for achieving the necessary operation and vertical positioning of the seat. The pivot pins are usually fixed on the device frame by a partial press deforming process, a so called riveting process. To assemble this known apparatus, the apparatus together with the heavy and large sized seat frame is set on the riveting machine, with the setting position of the overall structure being changed for securing each pin. The large number of parts and the difficulty associated with the riveting assembly process increase the manufacturing cost of the apparatus.
In light of the foregoing, a need exists for a vertical movement apparatus for a vehicle seat that is not as susceptible to the same disadvantages and drawbacks as those described above.
A need also exists for a vertical movement apparatus for a vehicle seat in which the number of linkage parts and pivot pins is minimized.
A still further need exists for a vertical movement apparatus for a vehicle seat that reduces or eliminates the need for a riveting process to attach the vertical movement apparatus to a vehicle seat.
According to one aspect of the present invention, a vertical movement apparatus for a vehicle seat includes a first bracket adapted to be secured on a floor side member, a second bracket arranged to be adjustable relative to the first bracket, a sector gear disposed between the first bracket and the second-bracket, and a braking mechanism having a pinion gear that meshes with the sector gear. The first bracket and the second bracket are pivotally connected to each other and the sector gear is pivotally connected to the second bracket and engages the first bracket via a slide member secured on the sector gear.
According to another aspect of the present invention, a vertical movement apparatus in a vehicle seat includes a first bracket adapted to be secured on a vehicle floor side member, a second bracket pivotally connected to the first bracket for pivoting movement relative to the first bracket, a rotatable sector gear mounted on a connecting shaft for pivoting movement relative to the second bracket, and a rotatable pinion gear meshing with the sector gear. A portion of either the sector gear or the connecting shaft engaging the first bracket to prevent the sector gear from pivoting relative to the first bracket.